With the growing environmental awareness of people, more and more bamboo products are being used because of bamboo's status as a renewable resource. However, bamboo products are not easily processed, in particular, slim tube-shaped bamboo products. Bamboo has large and uneven pores between the fibers that makes bamboo products difficult to paint. In the conventional painting process, a primer is first applied on the bamboo product and is then allowed to dry. Next, a putty is applied to fill in the pores of the primed bamboo product. After the putty hardens, the bamboo product is polished with emery paper. Subsequently, conventional paint is sprayed on the polished bamboo product and allowed to dry. Lastly, the painted bamboo product is varnished and allowed to dry. The conventional process is complicated and the production period is long; therefore, the painting costs are high. Furthermore, applying putty uniformly on the bamboo product is difficult.